From the Guidelines
Central canal narrowing should be evaluated with MRI lumbar spine without IV contrast as the initial imaging study due to its ability to accurately depict soft-tissue pathology and assess spinal canal patency. This approach is supported by the American College of Radiology Appropriateness Criteria, which recommends MRI for suspected cauda equina syndrome or progressive neurologic deficits 1.
When considering the diagnosis of central canal narrowing, it is essential to recognize the symptoms that may indicate a more severe condition, such as cauda equina syndrome (CES), which includes impairment of bladder, bowel, or sexual function, and perianal or saddle numbness 1. The most common cause of CES is lumbar disc herniation at the L4-L5 and L5-S1 levels, but other etiologies like neoplasm, infection/inflammation, spinal stenosis, and hemorrhage should also be considered 1.
Key points to consider in the evaluation and management of central canal narrowing include:
- The importance of urgent MRI assessment in patients presenting with new-onset urinary symptoms in the context of low back pain or sciatica 1
- The use of a single 3-D heavily T2-weighted fat-saturated sequence protocol as a rapid and highly sensitive tool for evaluating CES in the emergency department 1
- The potential role of CT lumbar spine without IV contrast in answering whether cauda equina compression is present, although MRI remains superior for characterizing the etiology of CES 1
- The consideration of CT myelography for surgical planning in patients with CES or significant spinal stenosis 1
In terms of management, treatment typically begins with conservative approaches, but the specific details of these approaches, such as the use of physical therapy, pain medications, or epidural steroid injections, should be guided by the clinical presentation and the results of the initial imaging evaluation 1.
From the Research
Central Canal Narrowing
- Central canal narrowing is a condition associated with lumbar spinal stenosis (LSS), which can cause significant symptoms and functional limitations 2.
- LSS can be congenital or acquired, and can affect the central canal, lateral recess, or other areas of the spine 2.
- The diagnosis of LSS can be made based on a clinical history of back and lower extremity pain, and confirmed with cross-sectional imaging such as computed tomography or magnetic resonance imaging (MRI) 3.
Treatment Options
- Nonoperative treatment options for LSS include activity modification, oral medications, and physical therapy 3.
- Multimodal care, including nonpharmacological therapies, education, and lifestyle changes, may be recommended for patients with LSS causing neurogenic claudication 2.
- Pharmacological therapies, such as serotonin-norepinephrine reuptake inhibitors or tricyclic antidepressants, may be considered for patients with LSS causing neurogenic claudication 2.
- However, the use of certain pharmacological therapies, such as pregabalin and gabapentin, has been associated with adverse events and limited efficacy in some studies 4.
Surgical Interventions
- Surgical interventions, such as decompressive laminectomy, may be effective in carefully selected patients with LSS who do not improve with conservative management 3.
- Lumbar fusion may be considered for patients with LSS and concomitant spondylolisthesis, but the precise indications for this procedure remain unclear 3.
- Minimally invasive interventions, such as spinal cord stimulation, may also be considered for select patients with LSS 5.